The present invention relates to an annular element intended to be placed between the two beads of a tubeless tire, mounted on a flat-base rim, one of the shoulders of which is removable; the tire is intended, in particular, for use on load handling vehicles. It also concerns the assembly of the ring, the tire, and the rim.
Ordinarily tires for load handling vehicles are mounted on flat rims, are tires which are cured by means of vulcanization bladders, known as "honeycombs", such as described, for instance, in U.S. Pat. No. 3,970,416, and are used with an inner tube and an annular protective element of slight thickness placed between said tube and the base of the rim. This annular element generally has axial ends or lips of suitable shape so as not to damage the inner tube.
Tires for handling vehicles in most cases have an internal form ratio H/S of at most 0.8 and frequently close to 0.5, H being the height of the inner cavity of the tire measured between the rim base and the point of the inner wall of the cavity furthest from the axis of rotation of the tire, and S being the maximum axial width of the inner cavity. It follows from this that damage may be inflicted on the inner tubes, particularly due to rapid wear of the tubes, which is incidental to the use of such tires.
Furthermore, these tires are generally mounted on flat rims formed of three elements, namely the rim base, which is integral with a first rim shoulder, the locking ring, and the second ring shoulder. When the rim is intended for use with a tubeless tire, it is possible to mount such a tire on such a rim with a sealing joint being provided between the bead of the tire and the rim on the side of the removable rim shoulder. Nevertheless, the fact that the dimensional characteristics of the rim have rather large tolerances, that these rims are frequently deformed and ill-fitted, and that the difficulties in positioning and maintaining a sealing joint in the correct position are numerous does not make it possible to obtain proper tightness in the mounting of a tubeless tire on a flat rim or a rim of the same type having three elements.